Semiconductor lasers having a so-called “ridge structure” are known. In that case, the semiconductor laser has a main body on which a strip having a reduced width is formed. The active zone that generates light radiation is arranged in the main body. Improved guiding of the light radiation along the longitudinal extent of the strip is achieved as a result of formation of the strip having a reduced width. The strip is covered with a passivation layer consisting of silicon oxide, for example, and has an optical refractive index of 1.48. Those index-guided semiconductor lasers exhibit guidance of the light radiation that is all the better, the larger the jump in the optical refractive index from the material of the strip to the material of the passivation layer.
There is nonetheless a need to provide a semiconductor laser having better guiding of the light beams.